European College of Equine Internal
Medicine Congress 2016 Abstracts
ECEIM Congress 2016 Abstracts
Schedule for Oral Presentations
Lecture Hall Fennia 1
Friday 13.30–14.30
13.30–13.45 Cathcart Exhaled carbon monoxide as a marker for lower airway inflammation in thoroughbred racehorses
13.45–14.00 Hermange Cytology of bilateral bronchoalveolar lavage fluids: comparison of pooled and individual samples 14.00–14.15 Losada-Floriano Evaluation of the predictive value of the external laryngeal ultrasound in detecting equine upper
airway disease
14.15–14.30 Barba In vitro cytokine production in response to equine influenza virus and Streptococcus equi subspecies zooepidemicus
Friday 15.00–16.30
15.00–15.15 Medina-Torres Immune response to intranasal modified-life EHV-1 vaccination in immunised equids
15.15–15.30 Banse Impact of phenylbutazone on gastric glandular prostaglandin concentration and ulcer score
15.30–15.45 Westermann Evaluation of a blood sucrose test for the assessment of gastric ulcers in warmblood horses aimed at field conditions
15.45–16.00 Khan Evaluation of the rectal route of fluid administration in horses
16.00–16.15 Bakos Effects of fasting on serum concentrations of lipid mobilisation and hepatic parameters in horses
16.15–16.30 Kolk Acylcarnitine profile in endurance horses with and without metabolic dysfunction
Lecture Hall Fennia 1
Saturday 13.45–14.45
13.45–14.00 Cudmore Blood culture isolates and antimicrobial sensitivities from 863 critically ill neonatal foals (2005–2014) 14.00–14.15 Theelen Differences in prevalence and susceptibility patterns of bacteria isolated from foals with sepsis cultured at
14.15–14.30 Freccero Feasibility of echocardiographic subcostal apical view in newborn foals: bidimensional and doppler aortic parameters
14.30–14.45 Hamerlinck Left ventricular function in the ageing horse Saturday 15.30–16.30
15.30–15.45 Broux Heart rate variabiliry parameters to detect atrial fibrillation in horses
15.45–16.00 Broux Pharmacokinetics and electrophysiological effects of different dosages of oral sotalol in horses: preliminary results
16.00–16.15 Dufourni Influence of orally administered sotalol hydrochloride on QT intervals at rest and in anesthetized horses after transvenous electrical cardioversion (TVEC)
16.15–16.30 May Transcranial magnetic stimulation unravels motor impairment in knuckling horses affected by aquired equine polyneuropathy
Schedule for Flash Presentations
Lecture Hall Fennia 2
Friday 10.00–10.30
1. Trachsel Trimethoprim-sulfadiazine has KV11.1 potassium channel blocking activity in horses
2. De Clercq Right cardiac monophasic action potential recordings in standing non-sedated horses
3. Mitchell Plasma homocysteine concentrations in healthy horses and horses with atrial fibrillation
4. Leroux Long term prognosis of moderate or severe left-sided cardiac valvular regurgitations in horses
5. Wittschorek Myocardial function in horses during general anaesthesia evaluated by pulsed-wave tissue doppler
echocardiography
6. Wittschorek Origin, laboratory results, therapeutic concepts and outcome of horses diagnosed with borna
disease infection in Bavaria, Germany
7. Kra¨geloh Studies on the absorption of hypoglycin A
8. Cerri Diagnostic value of serologic tests and seroprevalence of borreliosis in horses living in southern Belgium
9. Deniau Clinical, imaging and dynamic abnormalities in 4 cases of laryngeal dysplasia
10. Niedzwiedz Evaluation of serum cytokines levels in equine recurrent airway obstruction (RAO)
11. Pringle Comparison of sample site and diagnostic tests for determination of carrier state in horses recovered
from strangles
Lecture Hall Fennia 2
Saturday 10.00–10.30
1. Sutton The equine acute abdominal pain scale (EAAPS) for horses with colic: is it feasible?
2. Sgorbini Equine gastric ulceration syndrome (EGUS) in donkeys: gastroscopic findings and prevalence
3. Siegers Usefulness of three portable lactate measurement devices in horses
4. Mackenzie Evaluation of a whole blood, point of care coagulometer in horses
5. Mackenzie Effect of sampling technique on coagulation parameters in the horse: needle versus indwelling
intravenous catheter
6. vd Brom-Spierenburg Usefulness of a hand-held glucometer in horses
7. Morgan Glucocorticoid receptor in the equine pituitary in health and disease
8. Warnken Insulin signaling in various equine tissues under basal conditions and under acute stimulation by
glucose and insulin
9. Loschelder Evaluation of heartrate variability and serum cortisol levels during euthanasia in 40 horses
Accepted Posters
1. Arroyo Leukemia in horses: a case series
2. Barton The influence of cleaning, disinfection and drying methods on endoscope hygiene in equine medicine
3. Bezdekova Chronic pyloric disorders in horses: 47 cases
4. Bonelli Determination of salivary cortisol in donkey stallions
5. Bonelli Blood gas levels in newborn foals after normal and assisted delivery
6. Cesarini Use of a commercial high-fibre equine liquid diet for enteral tube feeding in horses: clinical experience
in 9 cases
7. Gehlen Endothelin-1 plasma concentration in horses with cardiac disease at rest and after exercise
8. Klein Targeted hygiene management system: rapid beneficial effects
9. Niedzwiedz Utility of histological examination of the bronchial mucosa in diagnostics of recurrent airway
obstruction (RAO) in horses
10. Pihl Non-strangulating intestinal infarction associated with strongylus vulgaris: clinical presentation and
outcome
11. Puschmann Final results on the impact of needle size and disinfection protocols on the bacterial contamination
of cadaver skin cores
12. Recknagel Does gastric juice ph influence gastric emptying? A preliminary study
Oral Presentations
EXHALED CARBON MONOXIDE AS A MARKER FOR LOWER AIRWAY INFLAMMATION IN THOROUGHBRED RACEHORSES. M.P. Cathcart1, S. Love2, T.D.H. Parkin2, K.J.
Hughes3, D.G.M. Sutton2. 1School of Veterinary Medicine, Fac-ulty of Health & Medical Sciences, University of Surrey, Guild-ford, UK,2School of Veterinary Medicine, College of Medicine,
Veterinary Medicine and Life Sciences, University of Glasgow, Glasgow, UK,3School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia
The aim of the study was to investigate whether associations exist between established markers of lower airway inflammation (LAI) and biomarkers in exhaled breath (EB), namely exhaled nitric oxide (eNO), exhaled carbon monoxide (eCO) and exhaled breath condensate pH (EBC pH). A convenience sample of Thor-oughbred racehorses presenting with poor performance and a clini-cal indication for respiratory secretion sampling were selected. EB was collected in impermeable bags and EBC was condensed at 70°C, prior to endoscopic recording of tracheal mucus scores (TMS) and TA/BAL fluid sampling. eNO and eCO were measured offline via chemiluminescence; EBC pH was measured using a standardised pH electrode. Associations between exhaled biomark-ers and TA/BAL cytological parametbiomark-ers were investigated via regression analysis and 1-ANOVA where appropriate. 25 horses were sampled. A significant association between eCO and TMS was observed (P= 0.019), with horses recording a TMS of 2 or above having significantly higher eCO compared to those with a TMS of 0 or 1 (P= 0.0476). eNO was detectable in only 16% of samples. Horses with neutrophilic LAI were found to have a sig-nificantly higher EBC pH (5.83 0.52) compared to those without (5.06 0.63; P = 0.01). The identification of associations between exhaled biomarkers and established markers of LAI provide sup-port for the application of EB and EBC analysis as non-invasive modalities in the investigation of LAI in Thoroughbred horses. Increasing sample size and inclusion of a control group will be required to provide quantitative and qualitative evaluation of these assays.
CYTOLOGY OF BILATERAL BRONCHOALVEOLAR LAV-AGE FLUIDS: COMPARISON OF POOLED AND INDIVID-UAL SAMPLES. T. Hermange1, S. Le Corre1, E. Richard2, A. Courouce-Malblanc1.1Oniris, Atlanp^ole, Nantes Cedex 3, France, 2LABEO Frank Duncombe, Caen Cedex 4, France
It has recently been demonstrated that bronchoalveolar lavage fluid (BALF) cytology from one lung does not forecast the other lung in the same horse. The aim of the study was to determine whether pooled BALF from both lungs was representative of indi-vidual samples. Twenty horses referred for respiratory troubles were included. BALF was collected from each lung using 250 mL of warmed isotonic saline. Cytological analyses of each individual BALF and isovolumetric pools were carried out in a blinded man-ner. Cell proportions were log-transformed and compared using ANOVA, with Dunnett’s post-hoc test. For each cell type, correla-tions between pooled and individual BALF were assessed by Pear-son coefficient, and agreement between samples by intraclass correlation coefficient (ICC). P< 0.05 was considered significant. Neutrophil proportions were significantly lower (P= 0.02) in pooled (22.6 22.7%) compared to right (26.2 26.4%) but not left BALF (23.0 22.8%). No significant difference was observed for other cell types. Significant correlations were noted between pooled and both right and left BALF for neutrophils (R= 0.97) and haemosiderophage/macrophage ratio (R= 0.99 and 0.86, respectively). Mast cell proportions were not significantly corre-lated (R= 0.25 and 0.20). Agreement between samples was moder-ate for mast cells (ICC= 0.72 and 0.66, respectively) and good for the other cell types (ICC> 0.93). Correlations and agreements for neutrophils and other cell types represent promising preliminary data about the relevance of investigating pooled BALF. Cytologi-cal confirmation of equine asthma might however become chal-lenging with regard to the low proportions of mast cells.
EVALUATION OF THE PREDICTIVE VALUE OF THE EXTERNAL LARYNGEAL ULTRASOUND IN DETECTING
EQUINE UPPER AIRWAY DISEASE. A. Losada-Floriano1,
A.-C. Doublet1, C. Mespoulhes-Riviere1, F. Rossignol2, A. Lechartier3. 1Clinique Equine
– Ecole Nationale Veterinaire d’Alfort– Maisons Alfort, France,2Clinique de Grosbois– Boissy
St Leger, France, 3Clinique Veterinaire Equine de Meheudin –
Ecouche, France
Equine Upper Airway Disease (EUAD) is a major cause of poor performance in horses. External Laryngeal Ultrasound (ELU) has been proposed useful for early detection of recurrent laryngeal neuropathy (RLN), with both quantitative and semi-quantitative methods correlating well with Resting Endoscopy (RE) findings. Furthermore, correlation between high-speed-tread-mill endoscopy and ELU for RLN has been demonstrated to be excellent. The purpose of this study was to (i) Determine the value of ELU in the early detection of EUAD, especially sub-clinical cases of RLN and (ii) screen horses for laryngeal abnormalities during exercise. One hundred and fifty seven yearlings from two yards entering training were evaluated whit both RE and ELU methods, RE findings were interpreted according to the Have-meyer system and ELU findings whit a semi-quantitative and quantitative system. A longitudinal follow-up over two years was performed using Overground Endoscopy (OGE) and ELU. OGE was performed to assess any laryngeal dysfunction (RNL and other abnormalities) and ELU was performed using the same method as for recruitment of cases. Ninety-eight follow-up exami-nations were performed, with the final evaluation scheduled for autumn 2016. None of the horses with normal ELU at recruitment developed RNL, however 25% developed Palatal Instability (PI). In the horses with abnormal ELU at recruitment 32% developed PI, 2% developed RLN and 29% developed others laryngeal dys-functions. ELU is a useful diagnostic method for evaluation of EUAD, however due to the low prevalence of pathological cases in this population further investigation is required to allow valida-tion of this technique in affected horses.
IN VITRO CYTOKINE PRODUCTION IN RESPONSE TO EQUINE INFLUENZA VIRUS AND STREPTOCOCCUS EQUI SUBSPECIES ZOOEPIDEMICUS. M. Barba1, J.M. Daly2.1
Fac-ultad de Veterinaria, Universidad CEU Cardenal Herrera, Valen-cia, Spain,2School of Veterinary Medicine and Science, University of Nottingham, UK
Equine influenza virus (EIV) is one of the leading causes of infectious respiratory disease in equids worldwide, and secondary bacterial pneumonia worsens the outcome. The mechanisms of synergy between respiratory viruses and opportunistic pathogenic bacteria such as Streptococcus equi subspecies zooepidemicus (SEZ) remain unknown. The purpose of the study was to develop an in vitro model to study cytokine response to EIV and SEZ co-infection. DH82a cells, a canine macrophage-like cell line, were infected with EIV strains Sussex/89 (full-length non-structural pro-tein 1 (NS1)) or Kentucky/5/02 (truncated NS1) or co-infected with Kentucky/5/02 and SEZ 1 hour or 24 hour apart. The mRNA cytokine expression was measured by quantitative RT-PCR and analyzed by one-way analysis of variance and Tukey’s multiple-comparison test. Cells infected with Kentucky/5/02 had higher IFNa expression at 24 hour post-infection (P = 0.02) and IFNb expression at 48 h (P = 0.013) compared to Sussex/89. Expression of TNFa and IL6 was higher after infection with Sus-sex/89 compared to Kentucky/5/02 at 48 hour post-infection (P= 0.046 and P = 0.015, respectively). Cells co-infected with Kentucky/5/02 and SEZ showed higher TNFa expression 6 hour post-bacterial infection, especially if co-infected 24 hour apart (P< 0.001), compared to cells only infected with Kentucky/5/02 or SEZ. Differences in the cytokine responses observed with differ-ent EIV strains agreed with in vivo studies. These preliminary results suggest that DH82a cells can be used as an in vitro model to investigate the role of the innate immune response in secondary bacterial infection, but the relevance of these results needs further confirmation.
IMMUNE RESPONSE TO INTRANASAL MODIFIED-LIFE EHV-1 VACCINATION IN IMMUNISED EQUIDS. C.A. Dum-rath1,2, L.S. Goehring1, C.P. Bartmann2, B. Wagner3, C.E. Med-ina-Torres1. 1Ludwig-Maximilians-University, Munich, Germany,
2EAZ 230 Bundeswehr, Bad Reichenhall, Germany, 3Cornell
University, Ithaca, NY, USA
EHV-1 vaccines provide some protection against disease. We investigated innate and specific, mucosal and humoral immune responses after intranasal modified-live virus (IN-MLV) adminis-tration in vaccinated horses (n= 12) and mules (n = 12). We hypothesised IN-MLV induces rapid local and systemic immune responses, which differ in horses and mules. Four months post-immunisation (inactivated vaccine) animals received IN-MLV. Starting on D-2, daily clinical data, q48 h nasal swabs and weekly serum samples were collected. D-2 and D14 virus neutralisation (VN)-titres were significantly higher in mules compared to horses. Mucosal Ig-gB, -gC and -gD were significantly higher in mules than horses on D-2 and D3. Mule Ig-gC and -gD decreased signifi-cantly by D1. All Ig increased signifisignifi-cantly between D1 and D3. In horses, a rise in mucosal Ig concentration was apparent but not significant. Unexpectedly, on D-2 one mule and one horse were EHV-1 PCR positive and complement fixation assay results were elevated. Strain-analysis demonstrated wild-type (WT)-EHV-1 infection. Therefore, result interpretation was confounded by natu-ral EHV-1 infection. Mucosal immunity was apparently boosted in horses and mules, albeit differently. Absence of an increase in VN-titres and of clinical disease despite EHV-1 infection and IN-MLV could be attributed to an existing solid immunity induced by vacci-nation. Whether interspecies differences in the immune response were due to heterosis in mules could not be determined, as the exact time point of WT-EHV-1 infection was uncertain. However, findings suggest that regular vaccination could prevent occurrence of clinical signs during EHV-1 infection.
IMPACT OF PHENYLBUTAZONE ON EQUINE GASTRIC GLANDULAR PROSTAGLANDIN CONCENTRATION AND ULCER SCORE. S.K. Pedersen1,2, A.E. Cribb2, E.K. Read2, D.
French1, H.E. Banse2. 1TD Equine Veterinary Group, Calgary,
AB, Canada,2Faculty of Veterinary Medicine, University of Cal-gary, CalCal-gary, AB, Canada
In equids, phenylbutazone at high doses has been demonstrated to induce gastric ulceration, primarily in the glandular portion of the stomach. In other species, NSAID-induced ulceration is associ-ated with decreased gastric prostaglandin E concentration. The mechanism of NSAID-induced glandular gastric ulceration in horses has yet to be determined. The purpose of this study was to compare gastric ulcer scores and mucosal prostaglandin concentra-tion in horses before and after administraconcentra-tion of phenylbutazone or placebo. Twelve healthy adult horses were enrolled following approval of the study by the institution’s animal care and use committee. Horses were randomly assigned to treatment (n= 6; 4.4 mg/kg phenylbutazone q. 12 hour for 7 days) or placebo (n= 6; 20 mL molasses q. 12 hour for seven days) groups. Before treatment and three and 7 days after initiation of treatment, gas-troscopy was performed and glandular gastric biopsies were
col-lected and frozen at 80°C. Glandular ulcer scores were
retrospectively assigned using a scale of 0–4 by two trained, blinded evaluators. Prostaglandin E concentration in biopsies was measured using a commercially available enzyme immunoassay. Prostaglandin concentrations were compared using repeated mea-sures analysis of variance. Ulcer scores were compared using a generalized estimating equation. One control horse was excluded based on a blinded glandular ulcer score of 3 before treatment. Prostaglandin concentrations increased over time (P= 0.005) but there was no effect of treatment (P= 0.88). Ulcer score did not differ between treatment groups (P= 0.48). These findings suggest that phenylbutazone at this dose and duration did not impair gas-tric glandular prostaglandin synthesis.
EVALUATION OF A BLOOD SUCROSE TEST FOR THE ASSESSMENT OF GASTRIC ULCERS IN WARMBLOOD HORSES AIMED AT FIELD CONDITIONS. C.M. Wester-mann1, L. van den Wollenberg2, H. Everts1, J.H. van der Kolk3,
G. Counotte2, D.A. van Doorn1.1Faculty of Veterinary Medicine,
Utrecht University, CM Utrecht, The Netherlands, 2De Gezond-heidsdienst voor Dieren, AA Deventer, The Netherlands, 3Swiss
Institute of Equine Medicine, Agroscope and University of Bern, Bern, Switzerland
Gastro-endoscopy is the gold standard for detecting equine gas-tric ulcers but its use in practice is limited. Recently, sucrose was put forward as convenient marker to assess gastric permeability. Presence of sucrose in the blood after oral application may serve as indicator for gastro-intestinal damage. Sucrose can be measured by GC-MS analyzing technique, but this analytical approach is not cost-effective. Therefore, the use of an enzymatic test kit (SCA20-1KT, Sigma) was studied as an alternative, indirect, cost-effective approach to analyze sucrose, enabling screening of sus-pected horses in field conditions. To achieve this, 21 horses that were presented as patients in several equine clinics in the Nether-lands, were allocated to 6 groups: gastric ulcer score of 0 vs.≥2 and in both gastric scoring groups 3 levels of oral sucrose applica-tion (0.75, 1.0 and 1.25 g/kg body weight). Gastro-endoscopy was preceded by a non-feeding (12 hour) and a non-drinking period (3 hour). Blood samples (serum tubes) were taken before (T0) and at 45 minutes (T45) after sucrose administration. The enzymatic test showed 90% sensitivity and 82% specificity and these values were even lower when only samples at T45 were considered (73 and 60%, respectively). Blood sucrose concentrations did not differ statistically between groups with and without gastric ulcers and the enzymatic method showed no correlation with the GC-MS method that was used as a control method and should therefore not be used for diagnosis of equine gastric ulcers. In addition, the GC-MS method was also unable to show a difference between groups.
EVALUATION OF THE RECTAL ROUTE OF FLUID
ADMINISTRATION IN HORSES. A. Khan1, G. Hallowell2, C. Underwood1, A. Van Eps1. 1School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia,2School
of Veterinary Medicine and Science, The University of Notting-ham, Sutton Bonington Campus, Leicestershire, UK
In horses, the intravenous (IV) route is preferred for rapid and direct fluid administration however is expensive and invasive. Nasogastric (NGT) administration is an alternative in patients without gastrointestinal obstruction, however prolonged tube placement can interfere with feeding and lead to pharyngitis. Fluid administration per rectum (proctoclysis) is widely used in other species including humans. The aim of this study was to evaluate its efficacy and safety in horses. Six clinically normal Standardbred geldings were used in a 4-way crossover study: each received 3 dif-ferent fluid treatments (intravenous, nasogastric and rectal) at 5 mL/kg/h and underwent a control period (no treatment) with water and feed withheld. Body weight was measured at baseline and 6 hour. Packed cell volume (PCV), total protein, albumin, electrolytes, lactate, urine specific gravity, vital parameters, gut sounds and central venous pressure was measured every 2 hour. Data were analysed non-parametrically and reported as median [IQR]. Rectal fluid administration was well tolerated. All fluid treatments caused changes consistent with haemodilution, includ-ing significant (P< 0.05) decreases in PCV with IV (5[2.75–8]%), NGT (5[2.25–7.25]%), and rectal administration (5[3.75–6.5]%), that were not present in the control period. There was a significant bodyweight decrease (4.25[2.1–5.7] kg) in the control period (P< 0.05) but not with any of the fluid treatments. Vital parame-ters and CVP did not change significantly. Rectal fluid administra-tion may offer an inexpensive, safe alternative to IV fluid administration, particularly when administration via NGT is not possible or contraindicated.
EFFECTS OF FASTING ON SERUM CONCENTRATIONS OF LIPID MOBILISATION AND HEPATIC PARAMETERS IN HORSES. Z. Bakos1, B. Toth2.1Department and Clinic of Equine
Medicine, University of Veterinary Medicine, Budapest, Hungary,
2Equi-Med Ltd., Nyıregyhaza, Hungary
The purpose of the study was to evaluate the changes in serum concentrations of lipid metabolisation and hepatic parameters in horses under controlled fasting. Our hypothesis was that the serum concentrations of free fatty acids (FFA), triglycerides (TG), blood urea nitrogen (BUN), total bilirubin (tBIL), gamma-glutamyl transferase (GGT), glutamate dehydrogenase (GLDH) and total bile acids (BA) increase, while the insulin concentration decreases
during fasting. Twelve healthy, adult horses were starved under supervision until they began to show detectable signs of catabo-lism. Physical examination was performed at 24 hours intervals during the first 72 hours, and then at every 12 hours. The first blood sample was collected when fasting started (T0). The follow-ing blood samples were taken 72, 84, 96, 100, 104, 108, 112, 116 and 120 hours later Variables of interest were measured from every sample. Descriptive statistics and repeated measures analysis of variance were used to evaluate the data. All horses tolerated 96 hours of starvation without complications. They developed only mild to moderate hypertriglyceridaemia between 72 and 96 hours of fasting. TG, FFA and BUN concentrations increased, and later decreased significantly (P< 0.05). Insulin concentration also increased significantly, while tBIL did not. Our results show that in contrast with previous assumptions, clinically healthy horses are not prone to catabolic crisis, and severe hyperlipaemia and hypoinsulinaemia does not develop after 96 hours of fasting. Based on these results it also seems that the marked elevation of indirect serum bilirubin concentration in clinically ill horses is not primarily caused by starvation.
ACYLCARNITINE PROFILE IN ENDURANCE HORSES
WITH AND WITHOUT METABOLIC DYSFUNCTION. J.H. van der Kolk1, S. Thomas1, N. Mach2, A. Ramseyer1, D. Burger1,
V. Gerber1, J-M. Nuoffer3. 1Swiss Institute of Equine Medicine, Agroscope and University of Bern, Bern, Switzerland, 2INRA, AgroParisTech, Universite Paris-Saclay, Jouy-en-Josas, France,
3
Universit€atsinstitut f€ur Klinische Chemie UKC, Bern University Hospital, Bern, Switzerland
Beta-oxidation is essential in fat metabolism and can be moni-tored with acylcarnitine profiling in blood as partly degraded fatty acids accumulate as carnitine esters. The current study was aimed to assess acylcarnitine profile by electrospray tandem mass spec-trometry in endurance horses regarded as relying fully on b-oxida-tion for energy supply with and without metabolic dysfuncb-oxida-tion. Ten Arabian horses (mean age 10.5 1.8 (SD) years) comprising 5 mares and 5 geldings were sampled prior and post a 160 km endurance race [CEIO or CEI***]. Another four Arabian horses (10.3 1.3 years) all geldings, who failed to finish the endurance race [CEIO/CEI***/CEI 90] for metabolic reasons were also sam-pled before and after abandoning. ANOVA was used for statistical analysis.There was a significant increase (P< 0.001) in post exer-cise acylcarnitine profile for both groups with those from the fin-ishers being significantly higher than those from the non-finfin-ishers in 17 out of 27 acylcarnitines in contrast to free carnitine. C10-car-nitine reached largest increase (+42 times) in the finishers post exercise. The post exercise values (average SD) for free and acetylcarnitine were 28.8 5.5 and 44.2 11.5 for the finishers and 19.2 9.8 and 26.7 10 µmol/L (P = 0.036 and 0.028) for the metabolically compromised horses, respectively. The presence of the whole acylcarnitine profile in serum following extreme endurance exercise indicates a proper functioning b-oxidation of fatty acids in horses with or without metabolic dysfunction. How-ever, the findings in the current study suggest that the bioavailabil-ity of carnitine in the former group might limit their performance. BLOOD CULTURE ISOLATES AND ANTIMICROBIAL
SEN-SITIVITIES FROM 863 CRITICALLY ILL NEONATAL
FOALS (2005–2014). L.A. Cudmore, N.M. Collins, J.B. Carrick, C.M.Russell. Scone Equine Hospital, Scone, NSW, Australia
The aim of this study was to evaluate the antimicrobial sensitiv-ity results of micro-organisms from blood cultures of critically ill equine neonates in the Hunter Valley, Australia. Retrospective analysis of microbial blood culture results from foals ≤7 days of age admitted to Scone Equine Hospital’s Clovelly ICU between 2005 and 2014 was performed. A total of 1333 foals less than 7 days of age presented to the ICU during the time period; 863 foals had a blood culture submitted. A total of 211 foals returned a positive blood culture result (211/863, 24.4%). A total of 228 organisms were isolated; 59.2% gram positive isolates (135/228), 39% gram negative isolates (89/228) and 1.7% anaerobic isolates (4/228). A total of 58 multiple drug resistant organisms were iden-tified (58/228, 25.7%); 67.2% gram positive organisms (39/58) and 32.8% gram negative organisms (19/58). A total of 36 isolates were sensitive to the combination of penicillin and gentamicin (36/ 137, 26.3%) and 70 isolates were sensitive to a combination of
ceftiofur and gentamicin (70/144, 48.6%). These results indicate gram-positive organisms are the most common isolate cultured from foals with sepsis in our ICU. These results are in contrast with a previously published study performed at our centre (1999– 2004), where a predominance of gram-negative sepsis and higher levels of antimicrobial sensitivity were apparent. These results also indicate reduced anti-microbial sensitivity (<50%) to commonly used first line anti-microbial broad-spectrum combinations. The low sensitivities to commonly used antimicrobials highlights the importance of performing blood cultures in neonatal foals. DIFFERENCES IN PREVALENCE AND SUSCEPTIBILITY PATTERNS OF BACTERIA ISOLATED FROM FOALS WITH
SEPSIS CULTURED AT HOSPITAL ADMISSION AND
AFTER >48 HOUR OF HOSPITALIZATION: 1990–2015.
M.J.P. Theelen1, W.D.Wilson2, B.A.Byrne3, J.M. Edman2, K.G. Magdesian2.1Utrecht University, Faculty of Veterinary Medicine,
Department of Equine Sciences– Internal Medicine, CM Utrecht, The Netherlands,2University of California, School of Veterinary Medicine, Department of Medicine & Epidemiology, Davis, Cali-fornia, USA,3University of California, School of Veterinary
Med-icine, Department of Pathology, Microbiology & Immunology, Davis, California, USA
This study evaluates differences in prevalence and antimicrobial susceptibility patterns between bacteria isolated from foals with sepsis on hospital admission and after>48 hour of hospitalization. Bacteria cultured from protected sites of foals<30 days of age and diagnosed with sepsis were included. The microdilution SensititreÒ procedure was used for susceptibility testing. Results of cultures collected on hospital admission were compared to those collected after >48 hour of hospitalization. Cluster robust standard errors and exact logistic regression were used for statistical analysis. In total 267 foals and 445 bacterial isolates were included. After >48 hour of hospitalization we found a significant decrease in bac-terial cultures positive for Actinobacillus spp. (19.8%:0.0%) and Streptococcus spp. (11.6%:4.3%) and a significant increase in bac-terial cultures positive for Acinetobacter spp. (0.6%:3.3%), Ente-rococcus spp. (4.8%:19.6%), Pseudomonas spp. (0.3%:7.6%) and Serratia spp. (0.3%:5.4%). Percentages of bacterial isolates suscep-tible to selected antimicrobial drugs decreased significantly after >48 hour of hospitalization (amikacin 68.6%:42.4%, ampicillin 69.2%:28.6%, ceftiofur 90.9%:49.4%, ceftizoxime 92.4%:59.3%, chloramphenicol 85.0%:44.6%, enrofloxacin 87.6%:66.7%,
gen-tamicin 68.6%:30.6%, imipenem 94.1%:77.6%, penicillin
39.5%:13.2%, tetracycline 77.5%:33.3%, trimethoprim/sul-famethoxazole 64.4%:22.4%, amikacin+ penicillin 90.9%:58.4%,
amikacin + ampicillin 93.7%:57.1%, amikacin + ceftiofur
93.7%:62.4%, gentamicin+ penicillin 86.6%:45.5%, gentamicin + ampicillin 87.1%:44.0%). Susceptibility patterns of bacteria cul-tured at hospital admission were more predictable than susceptibil-ity patterns of bacteria cultured after>48 hour of hospitalization. Repeated bacteriological culturing and susceptibility testing at standard intervals should therefore become routine in hospitalized foals with sepsis to be able to detect ongoing or hospital acquired infections and select effective antimicrobial drugs for treatment.
FEASIBILITY OF ECHOCARDIOGRAPHIC SUBCOSTAL
APICAL VIEW IN NEWBORN FOALS: BIDIMENSIONAL
AND DOPPLER AORTIC PARAMETERS. F. Freccero1, A.
Cordella1, G. Forni1, C. Castagnetti1, F. Dondi1, A. Lanci1, K.
Niinist€o2, M. Cipone1. 1Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy, 2Veterinary
Teaching Hospital, University of Helsinki, Helsinki, Finland The subcostal view has never been described in echocardio-graphic examination of foals, nor aortic velocities obtained from this site. Aim of this study was to evaluate feasibility of subcostal transducer site in newborn foals and compare aortic bidimensional and Doppler-derived parameters obtained with conventional echocardiographic views. The study enrolled 18 newborn healthy foals, aged 7 to 134 hours and weighted 40 to 64 kg. Echocardiog-raphy was performed in lateral recumbency, using a 1–5 MHz phased-array probe. Subcostal view (SC) was obtained from left recumbency, placing the transducer under the xiphoid and point-ing cranially through the liver in order to see the aorta vertically in the image. Pulsed-wave Doppler gate was always positioned just distal to the aortic valve. Aortic diameter (AD) at sinus of Valsava
was measured from right parasternal long-axis and SC views. Peak aortic velocity (PAV), velocity time integral (VTI) and expected pressure gradient (PG) were obtained by pulsed-wave Doppler spectra from left apex (LA) and SC views. Data were analyzed by Wilcoxon test for paired samples. No statistical difference was found in AD between different views (P= 0.06). PAV, VTI and PG obtained from SC were significantly greater than from LA position (P= 0.0001, P = 0.0005, P < 0.001). As reported in dogs, SC view provides an optimal alignment with aortic outflow, lead-ing to higher velocities on Doppler examination. We can conclude that subcostal view can be easily applied in newborn foals, and lead more reliable aortic flow velocities than conventional left api-cal one.
LEFT VENTRICULAR FUNCTION IN THE AGEING HORSE. P. Hamerlinck, S. Ven, G. Van Steenkiste, D. De Clercq, A. Decloedt, G. van Loon. Department of Large Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
Ageing results in increased left ventricular stiffness and thus impaired relaxation in humans and small animals. The goal of this study was to assess the effect of ageing on echocardiographic mea-surements of left ventricular function in horses. M-mode, 2D- and tissue Doppler imaging (TDI) echocardiography were used to mea-sure left ventricular dimensions, systolic time intervals and left ventricular systolic (S), early (E) and late (A) diastolic myocardial velocities in 10 young (5–8 years) and 11 old (>17 years) horses without cardiovascular disease. Results of both groups were com-pared using an independent t-test (significance: P< 0.05). The group of old horses showed a significantly higher left ventricular end-diastolic internal diameter measured from a short-axis M-mode image at chordal level (P= 0.02). The ratio of pre-ejection period to ejection time was significantly lower in old horses (0.17 0.06 vs. 0.22 0.04, P = 0.04). TDI showed a signifi-cantly lower E/A ratio in old horses, both at chordal (2.44 0.77 vs. 3.58 1.54; P = 0.04) and at papillary muscle (1.55 0.58. vs. 2.68 0.88; P = 0.002) level. Aged horses show reduced early diastolic and increased late diastolic left ventricular myocardial velocities, indicating impaired relaxation. Further research in a lar-ger population is needed for a more comprehensive quantification of left ventricular diastolic function in the ageing horse.
HEART RATE VARIABILIRY PARAMETERS TO DETECT ATRIAL FIBRILLATION IN HORSES. B. Broux, D. De Clercq, L. Vera, G. Van Steenkiste, A. Decloedt, G. van Loon. Depart-ment of Equine Internal Medicine, Ghent University, Merelbeke, Belgium
Atrial fibrillation (AF) is the most common clinically important arrhythmia in horses. Diagnosis can be suspected during ausculta-tion, but has to be confirmed with electrocardiography. After suc-cessful treatment, relapse is common. Heart rate monitors can be used in horses and may offer basic parameters for heart rate vari-ability (HRV). If HRV parameters can be used to diagnose AF, this would be an accessible diagnostic tool for both veterinarians and horse owners to monitor their horses for AF recurrence. The purpose of this study was to asses if HRV parameters can distin-guish between AF and sinus rhythm (SR). Therefore 6 HRV parameters were determined in 20 horses, both in AF and in SR, at rest (2, 5, 60 and 240 minute recordings) and during exercise (walk and trot, 2 minute recordings). Time-domain (SDRR, RMSSD and Triangular Index), frequency domain (LF/HF ratio) and nonlinear parameters (SD1 and SD2) were used. Results for the detection of AF were good (AUC> 0.8) for most HRV parameters. RMSSD, SD1 and LF/HF ratio yielded the best results (AUC> 0.9). Cut-off values with good sensitivity and specificity were set at 320 ms, 227 ms and 0.896 for RMSSD, SD1 and LF/HF at rest and at 92 ms, 65 ms and 1.126 at walk. Although results improved with longer recordings, short record-ings were sufficient. In horses with frequent second degree AV-block, which increased HRV, recordings at walk or trot are recommended. We concluded that HRV parameters can be used to monitor AF recurrence in horses that were successfully treated for AF.
PHARMACOKINETICS AND ELECTROPHYSIOLOGICAL
EFFECTS OF DIFFERENT DOSAGES OF ORAL SOTALOL
IN HORSES: PRELIMINARY RESULTS. B. Broux1, D. De
Clercq1, L. Vera1, G. Van Steenkiste1, A. Decloedt1, A. Watteyn2, M. Devreese2, S,. Croubels2, G. van Loon1.1Department of Large
Animal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium, 2Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
Arrhythmias are common in horses and sometimes require long term anti-arrhythmic therapy. Unfortunately oral anti-arrhythmic drugs for use in horses are currently scarce. In human patients and small animals, sotalol hydrochloride is often used for long term treatment. Little is known about pharmacokinetics and elec-trophysiological effects of sotalol in horses. The purpose of this study was to determine oral bioavailability of sotalol at different dosages in unfasted horses, and to investigate the effects on atrial (AERP) and ventricular effective refractory period (VERP). There-fore, 6 healthy, unfasted horses were given either 0, 2, 3 or 4 mg/ kg sotalol hydrochloride orally in a cross-over design. Plasma con-centrations and AERP and VERP (at 600 and 1000 ms basic pac-ing cycle length (BCL)) were determined at steady state. Oral availability of sotalol was variable within and between horses. At 2, 3, and 4 mg/kg maximum plasma concentrations of 711, 1016 and 2324 ng/mL were reached. At 1000 ms BCL, VERP increased by 17, 24 and 21% and AERP by 15, 23 and 17% at 2, 3 and 4 mg/kg, respectively. At 600 ms, VERP increased by 6, 15 and 6% and AERP by 15, 13 and 14%. Sotalol increased ERP, but, despite increasing plasma concentrations, higher dosages did not result in a progressive increase in ERP. Besides local sweating, no side effects were noted. We conclude that sotalol increases ERP in horses. Since oral absorption is variable, care should be taken when using high dosages.
INFLUENCE OF ORALLY ADMINISTERED SOTALOL
HYDROCHLORIDE ON QT INTERVALS AT REST AND IN ANESTHETIZED HORSES AFTER TRANSVENOUS ELEC-TRICAL CARDIOVERSION (TVEC). A. Dufourni, B. Broux, A. Decloedt, D. De Clercq, G. van Loon. Department of Large Ani-mal Internal Medicine, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
Immediately after cardioversion of atrial fibrillation, reverse remodeling takes place and suppression of atrial and ventricular premature beats is important in reducing recurrence rates. Sotalol hydrochloride is a potent, non-cardioselective b-adrenergic block-ing agent with class III anti-arrhythmic action which can be used for oral anti-arrhythmic therapy in horses. In human patients, it prolongs repolarization and the effective refractory period with a significant increase in QT interval. A retrospective cohort study was performed on 30 horses that underwent TVEC. Mean QT and RR intervals at heart rates between 35 and 45 bpm were compared between two groups. The first group (n= 15) did not receive any medication and measurements were made prior to TVEC and under general anesthesia after cardioversion. In the second group (n= 15), measurements were made before and after oral adminis-tration of 2 mg/kg of sotalol hydrochloride prior to TVEC and under general anesthesia after cardioversion. Results were analyzed using linear mixed models with Bonferroni correction for multiple comparisons (horse random factor, treatment fixed factor). Base-line mean QT interval (n= 30) was 493 39 ms. The mean QT interval did not increase significantly (P= 0.219) after sotalol treatment (518 48 ms). Mean QT intervals increased signifi-cantly under general anesthesia (688 46 ms, P < 0.001) and were even significantly longer in horses treated with sotalol (771 61 ms, P < 0.001). Compared to baseline, anesthesia pro-longed the QT interval by 39% in untreated horses and 57% in horses treated orally with sotalol hydrochloride. Excessive QT pro-longation is often considered to be a risk factor for life-threatening ventricular tachyarrhythmia.
TRANSCRANIAL MAGNETIC STIMULATION UNRAVELS
MOTOR IMPAIRMENT IN KNUCKLING HORSES
AFFECTED BY AQUIRED EQUINE POLYNEUROPATHY. A. May1, S. Hanche-Olsen2, G. Gr€ondahl3, L. Walendy1, K. Hultin J€aderlund4, K. Matiasek5, L. Goehring1. 1Equine Clinic, Centre
for Clinical Veterinary Medicine, Ludwig Maximilians University, Munich, Germany,2Equine Clinic, Norwegian University of Life Science, Oslo, Norway, 3Department of Animal Health and
Antimicrobial Strategies, National Veterinary Institute, Uppsala, Sweden, 4Small Animal Clinic, Norwegian University of Life Science, Oslo, Norway,5Section of Clinical and Comparative Neu-ropathology, Centre for Clinical Veterinary Medicine, Ludwig Maximilians University, Munich, Germany
Aquired Equine Polyneuropathy (AEP; Scandinavian knuckling syndrome), is a neurologic disease of Scandinavia that is character-ized by extensor weakness in metatarsophalangeal and, less fre-quently, metacarpophalangeal joints. A specific etiology has not been identified, but AEP appears to be linked to silage feeding. It affects all breeds/age groups and presents with variable outcome ranging from fatal disability to complete recovery over a 5–6 month resting period. Pathologically, AEP is an intermediate neuropathy with conspicuous Schwann cell pathology and loss of large myeli-nated fibers. As recent findings also suggest degeneration of upper motor neuron (UMN), we obtained transcranial magnetic evoked potentials (TcMEP) from omotransversarius, extensor carpi radialis, gluteus and tibialis cranialis muscles of a cohort of knuckling horses and clinically sound stable mates to clarify 1. the possibility of sub-clinical disease, 2. the specific contribution of UMN/LMN dysfunc-tion to the extensor dysfuncdysfunc-tion. Altogether 22 animals were included. All knuckling horses (n= 14) showed prolonged TcMEP latency times (LTs) of tibial cranial muscles (left 48.6 7.8, right 49.4 5.4). The non-neurological cohort could be subdivided into 5 animals with likewise increased LT (left 41.9 3.7, right 52.2 7.7) and 3 horses with LTs ranging within reference values (left 24.0 8.5, right 24.2 8.5). In summary, TcMEP results show that AEP has a significant motor component. It further proved feasible to detect subclinical conduction/transmission failure in seemingly unaffected animals and therefore is a sensitive tool to identify horses at risk and to stratify disease development amongst neurologically affected individuals.
Flash Presentations
TRIMETHOPRIM-SULFADIAZINE HAS KV11.1
POTAS-SIUM CHANNEL BLOCKING ACTIVITIY IN HORSES. D.S. Trachsel1,2, M.A. Tejada1, V. Grøsfjeld Christensen1, P.J.
Peder-sen1, J.K. Kanters3,4, K. Calloe1, R. Buhl2, D.A. Klaerke1.
1
Department of Veterinary Clinical and Animal Science, Faculty of Health and Medical Sciences, University of Copenhagen, Fred-eriksberg C, Denmark, 2Department of Large Animal Sciences, Faculty of Health and Medical Sciences, University of Copen-hagen, Taastrup, Denmark,3Laboratory of Experimental
Cardiol-ogy, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Koebenhavn N, Denmark, 4Department of Cardiology, Herlev and Gentofte University Hospitals, Niels Andersens vej, Hellerup, Denmark
Several pharmaceutical compounds, including Trimethoprim-sul-famethoxazole have been shown to increase the QT intervals in humans and therefore predispose to the acquired long QT syndrome (aLQTS), a well-known repolarization disorder associated with sev-ere ventricular arrhythmias. A common mechanism responsible for aLQTS is an interaction between drugs and K+ -channels, e.g. blocking of Kv11.1 channels. Trimethoprim-sulfonamides combina-tions are large specter antimicrobials commonly used in equine med-icine. However, these drugs have never been investigated for cardiac side effects in equines, despite the occasional reports of collapse or death following drug administration. The aim of this work is to investigate the effect of a commercially available trimethoprim-sulfa-diazine (TMS) combination on equine Kv11.1 channels. For this purpose, Kv11.1 channels cloned from equine hearts were heterolo-gously expressed in Xenopus laevis oocytes. Whole cell currents were measured by two-electrode voltage-clamp (TEVC) before and during drug treatment. TMS reduced Kv11.1 steady state-currents measured at 20 mV by 83% at a concentration of 10 mM. The half maximal blocking concentration was 3.74 mM (95% CI 2.9–
4.7 mM). Further, the voltage dependence of activation was affected by the compound, shown as a right shift in the current voltage rela-tionship. The blocking effect was not use-dependent. This data indi-cates that TMS is a potent blocker of equine Kv11.1 channels and by affecting K+ currents, TMS might prolong the repolarization in horses. However, further in vivo and in vitro studies are needed to assess the potential of this drug combination to induce aLQTS, asso-ciated severe arrhythmias and thus eventually cardiovascular inci-dents and/or death in horses.
RIGHT CARDIAC MONOPHASIC ACTION POTENTIAL RECORDINGS IN STANDING NON-SEDATED HORSES. D. De Clercq, B. Broux, L. Vera, G. Van Steenkiste, A. Decloedt, G. van Loon. Department of Large Animal Internal Medicine, Fac-ulty of Veterinary Medicine, Ghent University, Belgium
In human medicine, monophasic action potential (MAP) analysis by contact electrode gives highly accurate information about the electrophysiological properties of cardiac tissue. It is used to investi-gate dysrhythmias and the impact of certain drugs on the myocar-dium. Precise measurement of a total MAP duration is difficult, therefore the MAP duration is usually determined at a repolariza-tion level of 90% (APD90). The aim of the study was to make MAP recordings in the non-sedated, standing horse and to determine the APD90. In 6 healthy Warmblood horses, on two different days, an 8F quadripolar contact catheter (EasyMap MAP, Medfact, Ger-many) was passed through an introducer catheter in the jugular vein and placed under ultrasound guidance at the level of the tuberculum intervenosum or right atrial (RA) free wall, or in the right ventricu-lar apex (RV). A MAP was recorded during 15 cardiac cycles. The heart rate ranged between 30 and 42 bpm. The amplitude and APD90 were measured semi-automatically with a data analysis soft-ware program (LabChart 8, ADinstruments, France). Recording time ranged between 35 and 165 minutes. The catheter displaced easily with horse movements. The mean (SD) amplitude and APD90 were 263 39 ms and 5.67 2.2 mV in the RA (n = 180) and 472 26 ms and 8.39 6.62 mV in the RV (n = 180). The day-to-day variability was moderate. RA and RV MAP recordings can be successfully obtained in standing non-sedated horses with a moderate day-to-day variability. Excessive head and neck move-ments hamper the recording.
PLASMA HOMOCYSTEINE CONCENTRATIONS IN
HEALTHY HORSES AND HORSES WITH ATRIAL FIBRIL-LATION. K.J. Mitchell1, D. De Clercq2, G. van Loon2, C.C. Sch-warzwald1. 1Equine Department, Vetsuisse Faculty, University of Zurich, Switzerland,2Department of Large Animal Internal
Medi-cine, Faculty of Veterinary MediMedi-cine, Ghent University, Belgium Homocysteine (HCY) is an amino acid produced from methion-ine metabolism. Plasma HCY concentrations ([HCY]p) are ele-vated (>15 lM) in some people with atrial fibrillation (AF) and can predict the reoccurrence of AF after cardioversion. The aim of this study was to validate a commercially available HCY assay for use in horses, to develop a reference interval for [HCY]p and to compare [HCY]p in healthy horses and in horses with AF before and after cardioversion. Blood samples collected from healthy horses (n= 27) and horses with AF (n = 57; 32 of which were car-dioverted using transvenous electrical cardioversion [TVEC]) were analysed using an automated enzyme cycling assay (Homocysteine Cobas C, Integra, Roche). Linearity and precision of the assay were assessed, reference intervals calculated and [HCY]p compared between groups. The assay was precise (coefficient of variation 1.6–4.3%, n = 10 repetitions) and provided linear results (r = 0.99 for spiked and natural samples) for a range of HCY concentra-tions. The reference interval for [HCY]p was 1.7–7.9 lM. [HCY]p was 4.65 [1.3–8.9] lM (mean [range]) in healthy horses and 4.65 [1.14–10.1] lM in horses with AF (P = 0.59); and was 5.38 [1.67– 11.9]lM on the first and 4.85 [1.28–10.4] lM on the 4th–12th day after TVEC (P= 0.16). [HCY]p was not associated with reoccur-rence of AF (n= 8) (P = 0.86). This assay allows precise measure-ment of [HCY]p in horses. Unlike in people, [HCY]p is not increased in horses with AF and cannot predict AF reoccurrence. This might be due to differences in the underlying pathological mechanisms of AF development in people and horses.
LONG TERM PROGNOSIS OF MODERATE OR SEVERE LEFT-SIDED CARDIAC VALVULAR REGURGITATIONS IN HORSES. A.A. Leroux, A. Goudmaeker, A. Fraipont, C. Cesar-ini, C. Cerri, L. Lecoq, H. Amory. Equine Teaching Hospital, Department of Companion Animals and Horses, Faculty of Veterinary Medicine, University of Liege, Liege, Belgium
Mitral and aortic regurgitations (MR and AR) are common in horses. Unlike mild valvular regurgitations, long-term prognosis of moderate or severe MR and AR is suspected to be guarded since they might induce congestive heart failure (CHF). The aim of this study is to perform a long-term follow-up of horses with moderate or severe MR and/or AR to confirm this prognosis. Firstly medi-cal files of horses with moderate or severe MR and/or AR that had a follow-up, were retrospectively reviewed over a 15-years per-iod (2000–2015). Clinical and echocardiographic data of 25 horses with moderate or severe MR (16/25) or AR (8/25) or both (1/25) were considered. All horses had undergone 2 or more echocardio-graphic exams 6 months to 10 years apart. Eight horses developed CHF (4 MR and 4 AR) and all died/were euthanized. Diastolic left ventricular internal diameter, left atrial diameter and pul-monary artery diameter were/became above reference values in 17/ 25 horses but no significant difference was observed between the first and the follow-up measurements (Student’s t-test, P< 0.05). Secondly follow-up data of additional horses with moderate or severe MR was collected by telephone survey. Owners of 27 horses agreed to answer the survey 1 to 6 years after diagnosis. Ten horses with CHF had died, 3/27 had developed CHF, 10/27 had remained clinically stable and 4/27 had died of non-cardiac causes. Results of this study confirm that moderate or severe MR and AR carry a guarded to poor long-term prognosis as 40% (21/52) of the studied horses developed CHF.
MYOCARDIAL FUNCTION IN HORSES DURING GENERAL ANAESTHESIA EVALUATED BY PULSED-WAVE TISSUE
DOPPLER ECHOCARDIOGRAPHY. J. Wittschorek1, H.
Geh-len2. 1Clinical Center of Veterinary Medicine, Equine Medicine and Reproduction, Ludwig-Maximilians-University, Munich, Ger-many, 2Department of Veterinary Medicine, Equine Clinic,
Sur-gery and Radiology, Freie Universit€at, Berlin, Germany
The aim of this study was to evaluate myocardial function of the anaesthetized horse by pulsed-wave tissue Doppler imaging (TDI). Twenty-five heart healthy horses were selected that had been admitted for elective surgery. TDI measurements were per-formed before (T1), during (T2, T3) and after (T4) anaesthesia. A standardized anaesthetic protocol was used, which included seda-tion with a a2–adrenoreceptor agonist combined with an opioid, induction of anaesthesia with guaifenesin and ketamine, and inhaled isoflurane for maintenance. During anaesthesia all horses were kept in left lateral recumbency. The TDI parameters included the isovolumetric contraction (IVC) and the systolic (S) as well as the early (E) and late diastolic (A) maximal velocities. Parameters determined by TDI of the right ventricular wall velocities showed significant reductions comparing T1 to T3: A decreased by 50.6 23.1 % (P ≤ 0.001), S by 39.8 38.6 % (P ≤ 0.001) and IVC by 25.0 37.2 % (P ≤ 0.001). Comparing T1 to T3 on the left ventricular wall A decreased by 37.8 24.8 % (P ≤ 0.001) and S by 18.1 26.2 % (P ≤ 0.001). Comparing T2 to T3, signifi-cantly reduced parameters were measured, which indicates a nega-tive impact of the duration of anaesthesia on contractility. The results of the study indicate that TDI is a suitable imaging tech-nique during anaesthesia. A direct impact of general anaesthesia on the kinetics of the heart and negative effects on the contractility in heart healthy horses were registered.
ORIGIN, LABORATORY RESULTS, THERAPEUTIC CON-CEPTS AND OUTCOME OF HORSES DIAGNOSED WITH BORNA DISEASE INFECTION IN BAVARIA, GERMANY. J. Wittschorek1, K. Matiasek2, A. May1, L.S. Goehring1. 1Clinical Center of Veterinary Medicine, Equine Medicine and Reproduc-tion, Germany, 2Institute for Veterinary Pathology and
Neu-ropathology, Ludwig-Maximilians-University, Munich, Germany Borna Disease Virus (BDV) is an enveloped negative-stranded non-segmented RNA virus able to cause lethal encephalitis in equids. Occurrence is restricted to regions of continental Europe, specifically, Southern Germany, Switzerland, Austria and the
Czech Republic. In recent months we observed an increase in case admission possibly linked to habitat changes of the sylvatic reser-voir and vector, the bicolored shrew (Crocidura leucodon). Aim of this retrospective study is to raise awareness; to summarize clinical signs; diagnostics; laboratory results; possible therapeutic approaches and present outcome of horses diagnosed with BD. Between April 2013 and July 2016 BD was diagnosed in 15 horses (8 female, 1 stallion, 6 geldings) aged 3 months to 21 years (me-dian: 8 years) of various breeds. Cases originated from premises around Munich within a 120 km radius. A presumptive diagnosis was based on history and presentation with fever; lengthening periods of somnolence and stupor, with severe gait abnormalities (incoordination). Diagnosis was made by measuring BDV-specific serum (13/15) and in the cerebrospinal fluid antibodies (15/15), with CSF commonly displaying a lymphomonocytic pleocytosis. 9/ 15 horses were treated with dexamethasone (0.1–0.2 mg/kg once daily) resulting in a dramatic, short-lived improvement. 3/9 horses stabilized and were discharged. However, with time and lowered corticosteroid concentrations reappearance of clinical signs were noted with maximal survival of 10 weeks. All horses were eutha-nized a definitive diagnosis was made by hippocampal immunohis-tochemistry. In conclusion, BD is currently our most prevalent cause of encephalopathy in the horse with rare differential diagno-sis of hepatoencephalopathy and cholesteatoma.
STUDIES ON THE ABSORPTION OF HYPOGLYCIN A. T. Kra¨geloh1, J.-M.V. Cavalleri2, J. Ziegler3, M. Terhardt4, J.
San-der4, G. Breves1, A. Cehak1.1Department of Physiology, University of Veterinary Medicine Hannover, Foundation, Germany,2Clinic for Horses, University of Veterinary Medicine Hannover, Founda-tion, Germany,3Leibniz Institute of Plant Biochemistry, Halle,
Ger-many,4Screening Labor, Hannover, Germany
Hypoglycin A (HGA) was detected in blood of horses affected by atypical myopathy (AM). After oral uptake, degradation to the toxic metabolite methylenecyclopropylacetic acid (MCPA) is con-sidered as a prerequisite for the pathogenesis of AM. This study aimed to characterize the absorption of HGA along the intestinal axis and potential degradation within the intestine. Duodenual, jejunal, ileal and caecal mucosal tissues from five adult healthy horses were incubated in Ussing chambers in the presence of HGA. Mucosal disappearance, tissue uptake and serosal release of HGA were determined. Potential microbial degradation of HGA was investigated by Colon-simulation technique (Cositec). HGA concentrations were analysed by LC-ESI-MS/MS with Fmoc-Cl derivatization and those of MCPA by UPLC-MS/MS after butyla-tion. Furthermore, the effects of paraffinum perliquidum and dif-ferent adsorbents on HGA absorption were investigated. HGA was absorbed in the jejunum and the ileum. In the caecum and the duodenum, no significant mucosal uptake of HGA was detectable. Epithelial uptake of HGA in the jejunum was significantly reduced by addition of an adsorbent containing medicinal charcoal, kaolin, silica and oak bark. HGA metabolites were neither detected in samples of the Ussing chamber experiments nor in samples of the Cositec trial. Findings of the present study indicate that the major sites for intestinal HGA absorption are the jejunum and the ileum. The equine intestine might not be the predominant site for degra-dation of HGA. Furthermore, results indicate that oral adminis-tration of an appropriate adsorbent may be useful to prevent AM in horses and their co-grazers.
DIAGNOSTIC VALUE OF SEROLOGIC TESTS AND SERO-PREVALENCE OF BORRELIOSIS IN HORSES LIVING IN SOUTHERN BELGIUM. S. Cerri1, C. Meersschaert2, R.
Hou-ben1, P.H. Pitel3, H. Amory1. 1Faculty of Veterinary Medicine, Department of Companion Animals and Equids, University of Liege, Liege, Belgium, 2Laboratoires Reunis, Fleron, Belgium,
Caen, France
The aim of this study was to compare the sensitivity and speci-ficity of two commonly used borreliosis serologic tests in horses in Europe, i.e. an immunofluorescence (IF) and an ELISA test, using a Westernblot (WB) as reference standard, and to evaluate the seroprevalence of borreliosis in healthy horses living in the south-ern Belgium. In the first part of the study, the serum of 100 horses with a clinical suspicion of borrreliosis was tested using the 3 tech-niques. Using 1/512 as positive threshold, the sensibility and sensi-tivity of the IF test were 83 and 74%, respectively, and the
sensibility and sensitivity of the ELISA test were 83 and 78%, respectively. The ELISA test was therefore used to test 303 serums collected between April 2014 and April 2016 from healthy horses living in southern Belgium. A seroprevalence of 22% was observed in those horses with an evidence of age related effect (P-value= 0.02) on the presence of Borrelia burgdorferi antibodies. These results are in good agreement with previously reported results in other European countries and in northern Belgium. In conclusion, taking in account (i) the high seroprevalence of borre-liosis in healthy horses living in southern Belgium, as it is the cases in other European countries, and (ii) the low diagnostic values of the two most commonly used borreliosis serologic tests used by equine practitioners, this study illustrates the high need to con-vince Belgian equine practitioners to confirm the positive results of Borrelia burgdorferi before administration of an antibiotic treatment.
CLINICAL, IMAGING AND DYNAMIC ABNORMALITIES IN 4 CASES OF LARYNGEAL DYSPLASIA. V. Deniau, O. Bran-dernberger, F. Rossignol. Clinique Veterinaire de Grosbois, Domaine de Grosbois, Boissy Saint Leger, France
Laryngeal dysplasia linked to 4th branchial arch defect is a recognised syndrome in various breed of horses, recently docu-mented with MRI studies. We describe the clinical, imaging, and exercise endoscopy findings in 4 cases diagnosed between 2012 and 2016. One jumping warmblood (case 1) and 3 racing thoroughbred (cases 2 to 4) mares, aged 3 to 7 years, were presented with com-plaint of poor performance and respiratory noise. Laryngeal dys-plasia was suspected by palpation in 2 cases based on the detection of a unilateral gap between the upper cricoid and thyroid cartilages. Resting endoscopy revealed a rostral displacement of the palatopharyngeal arch in two cases and a grade 3 reduced ary-tenoid abduction either right-sided (case 1) or left-sided (cases 2 and 3). Radiography of the larynx in case 1 demonstrated the presence of air in proximal oesophagus. Ultrasound performed in cases 2 to 4 confirmed the absence of cricothyroid articulation and dorsal extension of the thyroid, either left-sided (cases 2 and 3) or bilateral (case 4). Exercise endoscopy performed in cases 2 to 4 revealed a collapse of the aryepiglottic and vocal folds, mild ros-tro-ventral displacement of the palatopharyngeal arch, and either left-sided (cases 2 and 3) or bilateral (case 5) grade C impaired arytenoid abduction. Dorsal displacement of the soft palate occurred in case 5. Right-sided laryngeal dysfunction was not the main endoscopic finding in this series compared to previous reports and association with left recurrent laryngeal neuropathy may represent a diagnostic challenge. In bilateral dysplasia, palpa-tion can be confusing.
EVALUATION OF SERUM CYTOKINES LEVELS IN
EQUINE RECURRENT AIRWAY OBSTRUCTION (RAO). A. Niedz´wiedz´1, H. Borowicz1, K. Kubiak1, Z. Jaworski2, M. Cegielski3, J. Nicpon1. 1Department of Internal Diseases with
Clinic for Horses, Dogs and Cats; Wroclaw University of Envi-ronmental and Life Sciences, Wrocław, Poland, 2Department of Horse Breeding and Riding, University of Warmia and Mazury, Olsztyn, Poland, 3Department of Histology and Embryology,
Medical University of Wroclaw, Wroclaw, Poland
Recurrent airway obstruction (RAO) represents a serious health problem and is classified as an allergic disease, where contact with an antigen induce airway inflammation, bronchial hyper-respon-siveness and airway obstruction. Previous studies have demon-strated the presence of the Th2 response in the lungs of human patients with asthma and horses with heaves. These cells are involved in the production of cytokines that regulate the synthesis of immunoglobulins. A total of 40 horses were evaluated: 30 horses with RAO and 10 healthy animals. The expression levels of IFN-a1, IFN-c, IL-1b, IL-2, IL-4, IL-13 and tumor necrosis factor alpha (TNF-a) were measured in the serum obtained from both groups during crisis, using commercially available ELISA tests. A comparison of quantitative variables was carried out using the Kruskall-Wallis test. The median level of IFN-c in the control horses was 36.4 pg/mL. In RAO-affected horses, the median IFN-c level was statistiIFN-cally different, and was 78.9, respeIFN-ctively (P< 0.0001). The median level of IL-13 in the control horses was 10.2 pg/mL, and there was a statistical increase in the level of IL-13 in RAO-affected horses. The median level of IL-IL-13 in the study
group was 65.55 pg/mL (P< 0.0001). The serum median IFN-a1, IL-1b, IL-2, IL-4, and TNF-a levels were similar in both groups. These results indicate a low variability of the levels of cytokines and a high frequency of their detection in serum samples from horses with RAO. Immune mechanisms involved in equine RAO are more complex than those defined by a simple Th1/Th2 dichotomy.
COMPARISON OF SAMPLE SITE AND DIAGNOSTIC
TESTS FOR DETERMINATION OF CARRIER STATE IN
HORSES RECOVERED FROM STRANGLES. J. Pringle1, M.
Venner2, L. Tscheschlok2, M. Rıihim€aki1.1Swedish University of Agricultural Sciences, Uppsala, Sweden,2Equine Veterinary Clinic,
Destedt, Germany
Approximately ten percent of horses recovering from strangles reportedly carry S. equi ssp equi (S. equi) silently in their guttural pouches (GP) for months to years. These silent carriers are a nidus for new outbreaks. Carrier detection requires analysis for S. equi in nasopharyngeal or GP lavages. As yet there are no data com-paring the carrier detection ability of these two methods; in partic-ular with introduction of improved diagnostic sensitivity by qPCR for S. equi. Two strangles outbreaks including 98 weanlings and 38 Icelandic horses were monitored for five and ten months respec-tively to detect silent carriers, using bacterial culture and qPCR on lavage samples from the nasopharynx and both GPs. Overall car-rier state and yield from the test method and sampling site were identified. Descriptive statistics were calculated. McNemars test was used to assess for differences in carrier detection between sam-pling sites with P< 0.05 deemed significant. Culture positive carri-ers were 3–13% (3/98 and 5/38 respectively), whereas qPCR positive carriers were 15–37% (15/98 and 14/38 respectively). Sig-nificantly more culture positives were from GP. All culture posi-tives were also PCR positive. Based on qPCR results both nasaopharyngeal lavage and GP lavage detected similar propor-tions of carriers. However, each were occasionally the sole positive sample for carrier identification. The qPCR findings suggest a higher level of strangles carrier state and that carriage of S. equi is not restricted to the GP. However, whether horses only qPCR positive to S. equi can infect na€ıve animals is unknown.
THE EQUINE ACUTE ABDOMINAL PAIN SCALE (EAAPS)
FOR HORSES WITH COLIC: IS IT FEASIBLE?. Y. Maskato1,
A. Dugdale2, E.R. Singer2, G. Kelmer1, G.A. Sutton1. 1Koret
School of Veterinary Medicine, The Hebrew University of Jerusa-lem, Rehovot, Israel,2Philip Leverhulme Equine Hospital, School of Veterinary Science, University of Liverpool, Leahurst campus, South Wirral, UK
Clinical decision making in cases of colic requires pain assess-ment. Visual Analog Scale (VAS) is considered the gold standard. The Equine Acute Abdominal Pain Scale (EAAPS), a behavior-based scale, has been shown to be significantly more reliable and equally valid in comparison to the VAS, in studies using film clips. In this study, the EAAPS was evaluated in clinical cases for the first time. Consensual, discriminant and predictive validity, as well as usability and feasibility were examined. Pain in 56 horses, pre-senting with colic at one of two referral hospitals, was assessed by veterinarians, veterinary students, and technicians, by using both the VAS and the EAAPS. The EAAPS demonstrated both good usability and feasibility: 78% of the participants replied that pain scoring was easy or very easy [Confidence Interval (95%CI): 40– 97)] and 67% that pain scoring was quick or very quick (95%CI: 30–93). Discriminate validity (between extreme groups of strong pain versus weak pain; as defined by the VAS score) of EAAPS was good (AUC= 0.87; CI: 0.77–0.97). Predictive validity was similar to the VAS regarding outcome (dead or alive) as well as regarding surgical or medical treatment. Regarding predictive validity for outcome, EAAPS [Area Under the Curve (AUC) = 0.69, CI: 0.54–0.84] versus the VAS (AUC = 0.80). Predictive validity for surgical or medical treatment, EAAPS (AUC= 0.68, CI: 0.54–0.81) versus the VAS (AUC = 0.69). Consensual validity of EAAPS compared to the VAS (agreement) was moderate (Weighted Kappa= 0.57; 95%CI: 0.44–0.69). In conclusion, the EAAPS demonstrated good usability, feasibility and validity in the referral hospital setting.
